Make sure to change the water layer's blending mode to "Hard Light"(To create some transparency effect)

STEP 8

Press CTRL+T/CMD+T to transform and resize the running water till it fits the water tap.

STEP 9

Create a layer mask for running water (Layer > Layer Mask > Reveal) to remove the excessive part of the running water.(Layer mask tool is used instead of eraser tool to avoid accidentally erasing parts of the main image)

STEP 10

After completing the layer mask, go to Level or Curve to adjust the color and contrast of the running water.